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Epilepsy in Women

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Epilepsy in Women, Contraception Selection in Seizure Disorder, Contraceptive Selection in Seizure Disorder, Antiepileptic Drug Interactions in Contraception, Catamenial Seizure, Antiepileptic Medications in Women, Teratogenic Risk of Seizure Medications

  • Associated Conditions
  1. Catamenial Seizure
    1. Occurs in up to 50% of women with Epilepsy
    2. Seizure related to Menstrual Cycle
      1. Onset of Menses due to Progesterone withdrawal
      2. Mid-cycle at Ovulation due to Estrogen surge
  2. Polycystic Ovary Disease
    1. Occurs in up to 40% of women with Epilepsy
    2. Subset related to Valproate
      1. Improves with medication change
  • Precautions
  • Antiepileptic Agents and Teratogenicity
  1. Women should not get pregnant while on most Seizure medications
    1. Antiepiletic agents significantly increase the risk of congenital malformation
  2. Lowest risk agents in women of child-bearing potential (lower Teratogenic potential)
    1. Lamotrigine
    2. Levetiracetam
  3. Moderate risk agents in women of child-bearing potential (Moderate Teratogenic potential)
    1. Carbamazepine
    2. Oxcarbazepine
    3. Phenytoin
  4. Highest risk agents in women of child-bearing potential (high Teratogenic potential)
    1. Valproic Acid
  5. Unknown Teratogenic risks
    1. Lacosamide (Vimpat)
  • Management
  • Contraceptive Selection in Epilepsy
  1. Precautions
    1. Highly effective Contraception is critical
      1. See Pearls above regarding risk of congenital malformation
    2. Many antiepileptic medications decrease efficacy of Oral Contraceptives (see Drug Interactions)
  2. Avoid Oral Contraceptives with antiepileptics that induce CYP P450
    1. Agents listed below under Drug Interactions render OCPs less effective
      1. Oral Contraceptive failure rate with these agents >6%
    2. Norplant (not available in United States) also less effective with these agents
    3. High-dose Estrogen may be needed to suppress Ovulation
      1. Use 50 ug Estrogen pill if OCP used for Contraception
  3. Avoid Oral Contraceptives with Lamotrigine (Lamictal)
    1. Lamotrigine clearance is increased in the presence of Estrogen containing Oral Contraceptives
  4. Avoid Depo Provera if possible
    1. Both Depo Provera and many anti-epileptics increase Osteoporosis risk
  5. Consider non-Hormonal Contraception: Intrauterine Devices
    1. Copper-T IUD may be preferred
    2. Mirena IUD (Levonorgestrel) has higher failure rate (1.1 pregnancies per 100 woman-years)
  1. Antiepileptics that induce P450 system (avoid with OCP)
    1. Carbamazepine (Tegretol)
    2. Ethosuximide (Zarontin)
    3. Felbamate
    4. Phenobarbital
    5. Phenytoin (Dilantin)
    6. Primidone (Mysoline)
    7. Oxcarbazepine (Trileptal)
    8. Topiramate (Topamax)
  2. Antiepileptics that do not affect OCP efficacy
    1. Gabapentin (Neurontin)
    2. Levetiracetam (Keppra)
    3. Lamotrigine (Lamictal)
    4. Tiagabine (Gabitril)
    5. Valproate (Depakote)
    6. Zonisamide (Zonegran)
  • Management
  • Pregnancy Planning
  1. See Preconception Counseling
  2. Discuss pregnancy planning >1 year in advance of planned pregnancy
  3. Consult neurology on transition to least Teratogenic agents
  4. Supplement Folic Acid
    1. Dose 0.4 mg/day up to doses as high as 4 mg/day in some cases
  • Resources
  1. North American Antiepileptic Drug Pregnancy Registry
    1. Women on antiepileptics should consider enrolling to allow for better studies on antiepileptic drug safety